[tz] Yukon to move to year-round PDT

[Brian Inglis]

On 2020-03-08 07:35, Robert Elz wrote:
>     Date:        Sun, 8 Mar 2020 03:12:57 +0000
>     From:        Chris Walton <Chris.Walton at telus.com>
>     Message-ID:  <8d0180be1f9648b09103043e21b0195a at BTWP000240.corp.ads>
> 
>   | Yukon Standard Time (YST) is officially UTC-9 as defined in section 35
>   | of the Canada's federal Interpretation Act.
> 
> According to that, that is unless it has been modified by a
> proclamation by the Govenor in Council (and since Yukon apparantly
> hasn't been using UTC-9 for some time, I'd suspect that has
> probably happened).

As that page states that it is current to date, but last updated in 2015, it
should be valid as of any changes made for the 2007 NA switch date changes, and
obviously does not dictate what practices occur within provinces and territories.

> But that act doesn't mention "YST" at all, nor does it in any
> way prevent anyone from using that abbreviation (or acronym, or
> whatever it is really called) for any purpose, with any meaning
> they like.   If I want to use it to mean Young Sexy Thing there's
> nothing there to stop me.
> 
> So:
>   | YST cannot be arbitrarily redefined to UTC-7 by anybody on
>   | this mailing list;
> 
> Of course it can, we can use whatever abbreviation that we consider
> appropriate.   I have no opinion on what that should be, I'm nowhere
> near Canada, but there is absolutely nothing there that requires or
> prohibits anyone from doing anything at all - it is simply an interpretation
> act, which specifies what certain phrases mean when used in other acts
> (in this case "standard time").
> 
>   | nor can it be redefined by the Yukon government.
> 
> Whether it is within their (current) power to choose the time in
> which they operate I have no idea, but there is certainly nothing
> in that act which prohibits them from doing anything they like.
> 
> Whether they have the ability to alter what standard time means
> for the purposes of federal (Canadian) acts & proclomations, I have
> no idea - that could have been delegated to them by some other
> instrument, or not.   But there's nothing in that particular act
> which limits whatever powers the provinces & territories might have
> to legislate with respect to how time should be counted for the purposes
> of those matters that are under their control.   Whether there is
> something elsewhere, I have no idea - I have never bothered to research
> how the Canadian legislative system works.

For the 2007 NA switch date changes, each province and territory had to change
its legislation, and tz db zone info was not updated until a province or
territory enacted their legislation (see archives about 2006).

> But if the Yukon territory shifts its clocks to UTC-7 year round, then
> I'd expect (if still required) a procolamation from the Govenor in Council
> stating that would be issued (unless for some obscure reason some other
> part of Canada actually cares what the clocks in the Yukon say, which
> frankly, I doubt).
> 
>   | Furthermore, I think that redefining YST is a bad idea because it
>   | would create ambiguity
> 
> The three(or whatever) letter TZ abbreviations are inherently ambiguous.
> Anyone who ever attempts to use them for any purpose whatever, other than
> giving a warm fuzzy feeling to humans deserves no sympathy at all when
> whatever they are doing fails miserably.
> 
>   | when dealing with old and new time stamps.
> 
> When dealing with time stamps, we know what the offset from UTC
> was from the date/time recorded, if we know in which timezone the
> timestamp applies (for which the abbreviation is not sufficient).
> That's what this project's data is all about, and why we collect
> all that historic information (rather than relying upon something
> deficient like a POSIX TZ string).
> 
> I understand that people have fixed opinions on what particular timezones
> should be called, and what offset from UTC they should represent, but
> things change - none of this has existed for very long (archeologically
> speaking) and what we consider to be something fixed and unchangeable today
> might be entirely different tomorrow.   PST might become UTC-7, YST might
> become UTC-7 as well - that we used to believe they were UTC-8 and UTC-9
> respectively means nothing at all.

Current official practice seems to be to use daylight saving time zone names in
summer, and standard time zone names in winter.
Practice on the ground may use those in effect in adjacent areas, as these
practices are usually for ease of commerce and/or communication, or maintain use
of the standard time zone name year round.
I don't believe we currently have any documented information about usage in
summer in NE BC, SK, or QC E of 65 W.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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